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watson
28th October 2006, 10:15 PM
Evening all,
Until my order from Neil arrives, I thought I would have a go at sealing with some shellac. Just as a practice run.
I've mixed up some Diggers shellac with their recommended stuff, and its really full of floating particles. (gunk really)
I'm sure I've read here something about filtering shellac, but a search of the forum comes up with nothing, so I tried it through some lab filter paper. 5 hours later I've got a few millilitres....tried a coffee filter paper and got gunk again.
Am I just dreaming, about filtering that is, or is there a recommended method?
Regards,
Noel

echnidna
28th October 2006, 10:18 PM
Use an old stocking

watson
28th October 2006, 10:25 PM
Thanks Bob,
just the clue required.
( Do I have to wait until she's finished with them??)
Thanks,
I'll try it in the morning.
Regards,
Noel

soundman
28th October 2006, 10:40 PM
I've found cheap paper dust masks excelent filters for thin stuff like recycled turps so should be good for shelac as long as it isn't too thick and jammy.
cheers

watson
29th October 2006, 07:55 AM
Thanks Soundman,
Love choices....just checked the original filtration, and overnight there's only about an 1/8" in the bottom of a coffee jar. I'll try that on a bit of scrap too.
Regards,
Noel

Iain
29th October 2006, 11:33 AM
Like Bob said, use an old stocking, half the fun is getting it:D :D
The 'gunk' is fairly big as a rule, bits of hessian etc, and the stocking will get rid of this easily, on my next batch I was going to try to put the shellac flakes in a stocking and immerse the lot in meths, save one stage and a bit of farting around.

ubeaut
29th October 2006, 12:09 PM
Go to Spotlight, Lincraft or any shop that sells material and get some VIOL or any of the really fine woven sheer nylon type material used for curtain or bridal veils etc. Most will do the job very well.

Much better then stocking as the stocking weave opens up when stretched, miles better than cotton or linen which will close up when wet.

We use very fine viol for all our straining the shellac runs through pretty freely although very thick stuff may clog the weave and need to be cleaned away from the surface, just scrape it with the side of a spoon this will clear the material and allow the liquid to flow again, you may need to do this a few times.

Don't try to filter it through a funnel with the material down in the funnel but stretch the material so as to leave it away from the sides of the funnel. This gives a greater surface area for the polish to drain through rather than than a restricted area that will clog easily.

Cheers - Neil:)

watson
29th October 2006, 04:24 PM
Thanks Neil,
Just knocked off ten minutes ago, and re-read the section in the Polishers Handbook, and the info I was searching for was in there (of course).
Access to too much info, without organisation..that's my problem!!!
The small amount I got through the lab paper I used today on a jig I had finished, and it glows! Not a viable filtration method though.
Regards,
Noel

kiwigeo
30th October 2006, 05:57 AM
I use the special paper funnels with built in filters that you can buy from paint shops. Crowies paint shops stock them in SA. They also stock tack cloths which are really handy for prepping prior to a shellac job.

kiwigeo
30th October 2006, 05:59 AM
The small amount I got through the lab paper I used today on a jig I had finished, and it glows! Not a viable filtration method though.
Regards,
Noel

Noel, did you put a fold in the filter before using it? A bit hard to explain without pictures put if you fold the funnel in half and then open it out again so theres a fold in one side it improves flow rate through the filter. It's a trick they hammered into me at uni during stage I chemistry.

watson
30th October 2006, 07:07 AM
Noel, did you put a fold in the filter before using it? A bit hard to explain without pictures put if you fold the funnel in half and then open it out again so theres a fold in one side it improves flow rate through the filter. It's a trick they hammered into me at uni during stage I chemistry.
G'day,
I actually used a multi-folded (pre-folded) paper that I used to use for removing micro-fine carbon from liquid. No wonder I only got a little through, I checked the box and they're a No.1. I'll also check the paint store funnels.
Thanks for the info,
Regards,
Noel

soundman
30th October 2006, 03:33 PM
Those spray painting filters are great (paper funnel with a filter in)
you can get them from any auto refinish supplier.
they are truly a fiddle saver and the mesh is micron rated so you know how big the holes are.
AND you don't need to cop a slap in the face to get them:D

But if its a slap in the face you want, I'm sure if you explain the situation the bloke down the panel beates supplies would oblige as part of the service:eek: :D :D

cheers

watson
30th October 2006, 05:46 PM
But if its a slap in the face you want, I'm sure if you explain the situation the bloke down the panel beates supplies would oblige as part of the service:eek: :D :D

cheers

Smirk, smirk.....probably true!!
Regards,
Noel

soundman
30th October 2006, 07:51 PM
The dust mashs are finer than the spray painting filters and the work OK in a funnel because the front of them has a corigation .

cheers